Hold down for a machine for fabricating a cushioning packaging strip

ABSTRACT

AN IMPROVED HOLD DOWN MECHANISM FOR A MACHINE FOR FEEDING, FORMING AND ADHESIVELY JOINING A SERIES OF INDEPENDENT SHEETS TO PROVIDE A CUSHIONING PACKAGING STRIP. THE MACHINE HAVING CONVEYOR DRIVEN FORMING BLOCKS OVERLYING THE JOINED SHEETS AND A BED PLATE OVER WHICH THE SHEETS TRAVEL TOWARD THE DISCHARGED END OF THE MACHINE. THE HOLD DOWN MECHANISM FIRMLY PRESSES AND HOLDS THE SAID SHEETS TOGETHER DURING THE SETTING OF THE ADHESIVE AND INCLUDES A SERIES OF PRESSURE SLATS, SECURED BETWEEN CHAINS, AND OVERLYING A RESPECTIVE FORMING-BLOCK SO THAT PRESSURE IS ENTERED THROUGH THE SAID PRESSURE SLATS ON THE FORMING BLOCKS.

March 1971 L. D. VAN ANTWERPEN HOLD DOWN FOR A MACHINE FOR FABRICATING A CUSHIONING PACKAGING STRIP 3 Sheets-Sheet 1 Filed April 7, 1967 INVENTOR LLOYD D. Van ANTWERPEN GEORGE w. WRIGHT. JR.

March 1971 L. D. VAN ANTWERPEN HOLD DOWN FOR A MACHINE FOR FABRICATING A CUSHIONING PACKAGING STRIP 3 Sheets-Sheet 3 Filed April 7, 1967 3o INVENTOR LLOYD. D.'Vn ANTWERPEN GEORGE W. WRIGHT; JR.

Patented Mar. 2, 1971 3,567,553 HOLD DOWN FOR A MACHINE FOR FABRICAT- ING A CUSHIONING PACKAGING STRIP Lloyd D. Van Autwerpen, Milwaukee, Wis., assignor to Menasha Corporation, Neenah, Wis. Filed Apr. 7, 1967, Ser. No. 629,242 Int. Cl. B31f 1/00 U.S. Cl. 156-471 4 Claims ABSTRACT OF THE DISCLOSURE An improved hold down mechanism for a machine for feeding, forming and adhesively joining a series of independent sheets to provide a cushioning packaging strip. The machine having conveyor driven forming blocks overlying the joined sheets and a bed plate over which the sheets travel toward the discharged end of the machine. The hold down mechanism firmly presses and holds the said sheets together during the setting of the adhesive, and includes a series of pressure slats, secured between chains, and overlying a respective forming-block so that pressure is entered through the said pressure slats on the forming blocks.

This invention appertains to a machine and process for fabricating a cushioning and shock absorbing packaging strip for frangible articles, and more particularly to new and useful improvements in the hold down mechanism for such machines to provide a firm holding and pressing of the sheets or strips to be joined.

The machine generally adapted for making cushioning packaging strips of the present invention is shown and described in Patent No. 2,504,473 issued Apr. 18, 1950 to Martin Van Antwerpen and entitled Machine for Fabricating a Cushioning Packaging Strip.

Broadly speaking, the machine was designed to bring together a series of sheets (3) to form a cushioning packaging strip which may be placed around the peripheral edges of frangible articles, such as the glass replacement parts for automotive articles and mirrors for bathroom cabinets etc. By referring to FIGS. 28 to 31 inclusive of the drawings, shown in the above mentioned patent, one use and general structure of the cushioning strip is apparent. The strip primarily consists of three sheets of material, a base sheet, an intermediate V-shaped sheet and an outer sheet having a V-projection overlying the V-projection of the intermediate sheet. All of these sheets are adhesively joined together and the outer or third sheet is notched to receive the peripheral edge of the article to be cushioned. The machine described in, the aforementioned patent therefore is constructed primarily so that the three independent sheets are brought together in the desired manner and firmly joined to provide the finished product. In the patent, the sheets are fed from hoppers 47, 48 and 49 but in actual use now these sheets come in rolls and are fed as a continuous sheet.

Therefore, by referring to FIGS. 2, 17 and 36 of the patent, it can be seen that the upper or third sheet is fed from the hopper 47 through a forming mechanism carrying forming blocks 78 which give the upper sheet the shape desired and the spaced V-projections. The intermediate sheet is likewise fed through forming mechanism carrying forming blocks to form smaller equally spaced V-projections and finally, at the lower portion of the machine the base sheets are fed. All of these sheets are brought together in a timed relationship so that the V- notches of the intermediate or second sheet will be received within the V-notches of the outer or third sheet and these three sheets are then moved through the hold down mechanism which holds or presses the sheets together after the adhesive has been applied to the respective faces thereof. In the patent this hold down mechanism is indicated broadly by the reference numeral 174. By referring to FIG. 17 of the patent it can be seen that this hold down mechanism includes a fiat plate which rests on top of the forming blocks and this plate is spring urged to put pressure on the blocks for the joining of the various sheets.

The original machine was built from Pat. No. 2,504,- 473, magnetic means was utilized to help draw the plate firmly against the forming blocks.

While the hold down mechanism shown and described in the aforementioned patent worked satisfactorily, it did not provide a uniform pressure throughout the entire dimensions of the sheets and since the sheets are now perforated or cut longitudinally to provide a number of smaller strips, it is important that pressure be placed on the entire width of the sheets while the adhesive is setting.

It is, therefore, a prime object of the present invention to provide an improved hold down mechanism for the machine which will provide a firm and even pressure throughout the entire width thereof, as the sheets progress through the mechanism.

Another important object of the present invention is to provide a slight modification in the forming blocks whereby the forming blocks cooperate with a driven chain carrying pressure slats which align with each individual forming block and press firmly on the same throughout the entire length of the hold down mechanism.

A more specific object of the present invention is to provide a projecting pin or pins on the pressure slats which fit into correspondingly aligned apertures in the forming blocks whereby the forming blocks will drive the chain mechanism carrying the pressure slats.

A further object of my present invention is to provide a modified pressure slat carrying depending fingers which are engaged by the leading edge of the forming blocks and which in turn are secured to the pressure slats for driving the hold down mechanism.

A still further object of the invention is to provide a friction means for securing either to the upper surface of the forming blocks or to the lower surface of the pressure slats a rubber member which frictionally engages the opposing surface to drive the hold down mechanism and which friction means can be well adapted to any of the various modified forms of this invention.

A salient feature of the present invention resides in a modified form whereby the pressure slats may be eliminated and wherein a series of chains overlying the forming blocks are provided, the outer stretches of which are positioned in close proximity to the outer peripheral edges of the width of the sheet material being joined, and novel longitudinally extending pressure members are provided which rest upon the chains and firmly press the chains and forming blocks against the sheets to be joined.

A further object of the present invention is to provide means whereby the longitudinally extending pressure means are spring pressed against the chains and wherein these pressure members may be mounted on transversely extending supports which in turn are resiliently mounted by a spring means constantly urging supports in a downward direction.

Another object of the present invention is to provide means whereby the transversely extending support is rigidly secured to the frame of the machine and the resilient spring means is mounted between the support member and the longitudinally extending pressure member.

Still another object of the present invention is to provide modifications in the hold down means having longitudinally extending pressure members wherein rollers 'may be secured to the upper surface of each forming block and wherein the longitudinally extending pressure member engages the rollers for firmly pushing the forming block against the sheets being joined and against the flat bed of the machine. The rollers may also be mounted on the longitudinally extending pressure members.

A still further object of the invention is to provide new and useful improvements in the hold down mean for a machine for fabricating a cushioning packaging strip which is relatively simple in construction, reliable in its operation, and not liable to get out of order.

With these and other objects in view, and to the end of attaining any other advantage hereinafter appearing, this invention consists in certain features of construction, combination and arrangement of parts, hereinafter described, pointed out in the claims, and illustrated in the accompanying drawings, in which FIG. 1 is a fragmentary vertical section taken through the machine shown and described in Pat. No. 2,504,473 and particularly illustrating one preferred embodiment of the hold down mechanism;

FIG. 2 is a fragmentary transverse section on an enlarged scale through the hold down mechanism shown in FIG. 1 of the drawings, the section being represented by the line 2--2 of FIG. 3;

FIG 3 is a fragmentary horizontal section through one of the sprocket means and chain drive for the hold down mechanism, the drawings being on the same scale as illustrated in FIG. 2, the section being represented by the line 33 of FIG. 2 of the drawings;

FIG. 4 is a perspective view of the joined sheets illustrating the type of cushioning packaging strip produced by the machine;

FIG. 5 is an enlarged fragmentary vertical section similar to FIG. 3 of the drawings, but illustrating modified form for driving the hold down mechanism through the forming block and drive;

FIG. 6 is a fragmentary transverse section illustrating that form of the invention shown in FIG. 5 of the drawings, the section being taken on the line 66 of FIG. 5, looking in the direction of the arrows;

FIG. 7 is an enlarged fragmentary horizontal section through the forming blocks and pressure slats showing a still further modification in the drive means for the hold down mechanism;

FIG. 8 is a fragmentary vertical section showing a still further modification in the hold down mechanism, certain parts being broken away and in section to illustrate further details in its construction;

FIG. 9 is a fragmentary transverse vertical section taken on the line 9-9 of FIG. 8, looking in the direction of the arrows;

FIG. 10 is a fragmentary transverse vertical section similar to FIG. 9 of the drawings, but illustrating a still further modified form of the hold down;

FIG. 11 is a fragmentary transverse section through one of the longitudinally extending hold down pressure members illustrating a further modification, and

FIG. 12 is a fragmentary vertical section similar to FIG. 11, but illustrating another modified form.

Referring now to the drawings in detail, wherein similar reference characters designate corresponding parts throughout the several views, the letter H generally indicates one type of the improved hold down means for adhesively joining the sheets 10, 11 and 12 together as they move from the machine in proper timed relation so that the intermediate sheet 11 has its projections 13 in alignment with the V-projections '14 of the outer sheet 12. The manner of forming the projections 13 on intermediate sheet 11 and V-projections 14 on sheet 12 is substantially similar to that shown and described in the aforementioned patent No. 2,504,473 of Martin Van Antwerpen, and therefore, need not be again described in detail.

In any event, attention is now directed to FIG. 4 of the drawings, wherein a fragmentary perspective view of the type of cushioning packaging strip is illustrated and it can be seen that the same includes the aforementioned base strip 10, the intermediate strip 11 and the outer strip 12 and that the intermediate strip is formed with spaced projections 13 which are in alignment with and are received partially within the V-shaped projections 14 of the outer strip 12. These strips are also slotted as illustrated by the reference numeral 15 and preferably weakened or cut longitudinally as at 116 to provide when desired individual strips with aligned notches in the V-projections. These notches receive the peripheral edges of frangible articles as illustrated in the aforementioned patent, primarily FIGS. 28 to 31 thereof. Of course, there are many other and varied uses for this cushioning packaging strip which is known in the trade as Sus Rap.

Therefore, these sheets must be firmly bonded together and to accomplish this before the sheets are moved together toward the hold down mechanism H, the respective surfaces of sheets 10, 11 and 12 are coated with a quick setting adhesive and therefore, it is necessary that these sheets be firmly held together for a short period of time while the adhesive sets.

The drive forthe forming blocks 16 is by means of spaced chains 17 of a general conventional construction having outer links 18 and inner links 19 joined by cross pins 20 noted in particular in FIG. 6 of the drawings. These chains carry the spaced transversely extending forming blocks 16 and are driven similarly to the blocks of conveyor belt 88 in patent 2,504,473 as described in the patent. Base sheet 10 is pulled from its roll to a position where it engages the bottom surface of the intermediate sheet 11 and generally at a point designated by the reference numeral 20 these sheets are all brought together and the forming blocks for the upper sheet 12 remain in position through the entire travel of the sheets through the hold down mechanism H and are then moved from the sheet at the very front of the machine (not shown). The novel hold down mechanism generally includes a pair of spaced sprocket wheels 21 splined or otherwise secured to shaft 22 and over which is trained a pair of spaced chains 23 and 24 respectively, and these chains are held taut by suitable belt tighteners and/or guide tables not shown. The chains are likewise trained over a pair of spaced sprocket wheels 25 splined to the shaft 26 and firmly secured between the chains 23 and 24 are a series of pressure slats 27 and these slats are spaced in such a manner that they will align with corresponding forming blocks 16 carried between the drive chains 17. Normally, it is desirable that the sprocket wheels and chains of the hold down mechanism H not be driven through the forming block drive. It is noted to provide a positive drive for the chains 23 and 24 carrying the pressure, slats 27, projecting pins 28 are provided in each pressure slat 27. It should be understood that only one pin may be provided but for stability it is preferred that two spaced pins be provided positioned approximately adjacent the end termination of the width of the sheets being joined and thus, as shown in FIGS. 2 and 3 of the drawings, a pair of such pins 28 are provided and each forming block 16 is likewise provided with an aligned opening or aperture 29, into which the pin 28 will project. Thus, it can be seen that as the forming blocks secured to the drive chains 17 proceed through the hold down mechanism, the pins situated on the pressure slats will engage in the appropriate apertures and the entire hold down mechanism will be driven and moved in the direction of the arrows in FIG. 1.

Since the chains 23 and 24 respectively are kept taut between the pairs of sprocket wheels 21 and 25, respectively, pressure will be placed between the pressure slats on forming blocks 16 and through the respective sheets 10, 11 and 12. This is particularly true since the sheets are firmly engaged between bed plate 30 of the machine proper and thus, it can be seen that these sheets are firmly held together throughout the entire length of the-hold down mechanism and particularly pressure is placed on these sheets between shafts 22 and 26, and primarily throughout the entire width of the sheets since, as shown, the pressure slats extend well beyond the outer peripheral edges 31 of the joined sheets.

In FIG. 3 of the drawings, in order to allow for a slight differential in the alignment between the forming blocks 16 and pressure slats 27, the apertures are generally of a greater circumference than the pins to allow considerable play between the circular walls of the apertures and to accommodate the circumference and curvature of the sprocket wheels 21. Thus, the pin is engaged by the inner portion 35 of the aperture 29, and as it is driven room is allowed for movement of the pin within the aperture while assuring constant engagement with the walls of the aperture and forming blocks 16.

Attention is now directed to FIGS. 5 and 6 of the drawings, wherein there is illustrated a modified means for driving the hold down mechanism. In this form of the invention, the forming blocks 16' are of a general rectangular shape to allow space between the V-projections 14 of sheet 12 and the leading edge 36 of the forming block. The reason for this is that instead of projecting pins, depending fingers 37 are secured to the trailing edges of each of the pressure slats 27. If desired, as in the previously described form, only one depending finger may be used, but preferably a pair are utilized similar to the pins 28 and spaced substantially the same. In this form of the invention, the driven forming blocks 16' engage the projecting fingers 37 and pull the chains 23 and 24 respectively through the hold down portion and pressure is placed upon the sheets in much the same fashion as that shown in FIGS. 1 to 3 of the drawings.

FIG. 7 illustrates still another modified form of driving chains 23 and 24 carrying the pressure slats 27 through the hold down position and in this form of the invention, blocks 16 will again be rectangular in shape although it is conceivable that they may be shaped the same as blocks 16 in FIGS. 1 to 3. In any event, secured to the upper surface of blocks 16' or lower surface of pressure slats 27, is a strip of resilient friction material and blocks 16 and pressure slats 27 are in exact alignment and the friction of the friction strip 38 will drive the hold down means described in either FIGS. 1 to 3 or 5 and 6 as an additional feature.

Attention is now directed to FIGS. 8 and 9 of the drawings, wherein still another modified form is illustrated for holding, pressing and adhesively joining the sheets. In this form of the invention the transversely extending pressure slats are eliminated and in lieu thereof a series of chains 40 is provided. In the preferred form, three chains may be used as shown primarily in FIG. 9. These chains overlie and are in direct contact with the upper surface of the forming blocks 16" which are carried by the drive chains 17 in the manner previously described. Again, the various sprocket wheels 21 utilized are driven by means of dirct contact with the forming blocks. In order to exert pressure on the chains and to firmly hold the chains against the forming blocks throughout the length of the hold down a series of longitudinally extending pressure members 41 are provided and these members are in alignment with a respective chain 40 and preferably angle iron secured firmly to transversely extending carrying bars 42. These carrying bars are in turn secured to the frame F proper of the machine. In the form illustrated by FIGS. 8 and 9 of the drawings, the transversely extending bars 42 are spring urged in a downward direction and therefore are carried by upstanding pairs of spaced bolts 43 around which springs 44 are placed. Each spring is held to the bolts by means of threaded nuts 45 and thus, tension on the carrying bars 42 can be adjusted by means of the nut 45 and greater or lesser force exerted by springs 44. The longitudinally extending pressure members 41 at the end terminations are rounded or pointed as indicated by reference numeral 46 so that the pins 47 will be engaged by the lower surface of the pressure members and thus an even pressure is exerted on each individual forming block throughout the entire hold down mechanism.

' If desired, the transversely extending cross members 42 could be rigidly carried by the frame F and this form of the invention is illustrated in FIG. 10 of the drawings, wherein cross members 42 are adjustably received over bolts 43 by the provision of adjusting nuts 45, one above and one below the horizontally extending wall 48. In this form of the invention, the longitudinally extending pressure members 41 are T-shaped with the depending vertical leg 49 thereof engaging the pins 47 of each respective chain 40. Each member has rigidly secured thereto a vertically extending pin 50 and a spring 51 is positioned between the transverse bar 40 and pressure member 41 to constantly urge the pressure member against the spring in the manner described. Thus, each longitudinally extending pressure member 41' is independently spring urged against its respective spring and again, pressure therefore is exerted on each forming block throughout its entire travel through the hold down mechanism and the sheets are firmly bonded together prior to their moving from the machine.

It is also possible that in the forms of the invention shown and described in FIGS. 9 and 10, a series of chains 40 could be entirely eliminated together with the sprocket wheels 21 and 24 respectively, and that the spaced rollers (FIG. 11) could be secured firmly to the upper surface of each forming block 16" and these rollers are designated by the reference numeral 50' and are preferably of the type having side guide flanges 51 so that the longitudinally extending pressure members 41 carried by the transversely extending bars 42 will engage between the flanges and firmly press each individual forming block 16" against the sheets riding on the base bed 30.

As illustrated in FIG. 12 of the drawings, the rollers having flat peripheral surfaces 52 could be mounted on the vertical leg 53 of the longitudinally extending hold down members 41 and these rollers would engage the upper surface 54 of the respective forming bar as the sheets proceed through the hold down mechanism and thus the sheets will be firmly bonded.

While it is not absolutely necessary, I may provide a permanent magnet under the base bed 30 or that portion of the base bed 30 over which the sheets move could be magnetized, and this would further draw the chains and metal hold down portions of the mechanism firmly toward the bed and against the forming blocks thus providing an even greater pressure for the joining of the sheets.

Therefore, while I have shown and described certain specific embodiments of the invention, it will be readily understood that these are merely for the purpose of illustration and description, that various other forms may be devised and that changes may be made in the propor tions and minor details of construction without departing from the spirit of the invention or scope of the appended claims.

What is claimed as new is:

1. In combination with a machine for feeding, form ing and adhesively joining a series of independent sheets to provide a cushioning packaging strip of the type having conveyor driven forming blocks overlying the joined sheets and a bed plate over which the sheets travel toward the discharge end of the machine of a hold down mecha nism for firmly pressing and holding said sheets together during the setting of the adhesive, including pairs of spaced sprocket wheels secured to said machine above a respective stretch of said conveyor carried forming blocks, drive chains connecting said respective pairs of sprocket wheels, a series of pressure slats secured be tween said chains, each slat being so constructed and arranged as to overlie a respective forming block, means a 7 for exerting pressure on said forming iblocks through said pressure slats during the travel of the sheets through said hold down mechanism, and means for driving said sprocket wheels and chains from said conveyor carried forming blocks.

2. A hold down mechanism as set forth in claim 1, wherein said means for driving said pressure slats includes pairs of aligned spaced pins projecting from one surface of said pressure slats and correspondingly aligned apertures in said forming blocks whereby when a respective pressure slat contacts a respective forming block said pins will enter said apertures.

3. A hold down mechanism as set forth in claim 1, 'Wherein said means for driving said pressure slats includes spaced projecting fingers on one edge of said pressure slats being so constructed and arranged as to be UNITED STATES PATENTS 2,737,227 3/1956 Brummel 161146X 2,877,823 3/1959 Van Antwerpen et al. 156471 2,983,636 5l1961 Runton 156210X JOHN T. GOOLKASIAN, Primary Examiner H. F. EPSTEIN, Assistant Examiner US. Cl. X.R. 93-1, 84 

